In the recent past, Wisconsin has experienced significant extreme weather events, placing a toll on all population health related sectors of society from agriculture to business, housing, and human health. The overall goal of this research project is to develop predictive models of both current and climate change-related precipitation variability that poses environmental health risks at a statewide scale required for public health preparedness. Specifically, we will: 1) Establish a 'health impact assessment'framework and engage key experts and stakeholders from across Wisconsin so that end-users of our predictive models and policy decision makers may be included at the start of this project;2) Determine threshold levels or climate pattern signatures defined as 'hazardous'precipitation events and develop predictive models of environmental contamination and subsequent incidence of gastrointestinal illness linked to these hazardous events. Methods will be developed to: a) identify and define hazardous precipitation events with significant public health outcomes using National Centers for Environmental Prediction's (NCEP) North American Regional Reanalysis (NARR), which provides output at 32 km resolution of temperature, precipitation and other variables at three hour intervals from 1979-2007;b) examine the correlation between sewage virus presence in surface water and climate-related parameters in the Menomonee River Watershed;and c) explore the association of hazardous precipitation events and rates of acute gastrointestinal illness by local jurisdictions (zip codes) across the state using statewide emergency department visit data from 2002-2008. 3) Using advanced climate-model downscaling methods, project the future public health burden of hazardous precipitation events in Wisconsin for the middle and late 21st century. We will use both statistically and dynamically downscaled climate model outputs to: a) identify areas within the state that will most likely be impacted by extreme weather-related events;b) use output to analyze public health preparedness and response capabilities across the state;and c) identify areas for future mitigation and adaptation to guide policy decisions. The integrative and interdisciplinary nature of this effort brings together key expertise from across the fields of climatology, environmental public health, water resources, microbiology, virology, fecal indicator development, and statistical modeling. The Wisconsin Department of Health Services'(DHS) will leverage its existing climate change and health research with the University of Wisconsin-Madison and other research collaborators in the state. - Relevance This research project is addressing public health in multiple ways related to risks posed by current variability in precipitation, along with future climate change projections. First, we are advancing public health practice and research in the state of Wisconsin by conducting a public health impact assessment and engaging key stakeholders early on in the process. Second, we are improving early predictive capability for health decision makers by investigating weather-related etiology of gastrointestinal illness. Third, we are expanding the knowledge base by developing public health relevant tools from newly available downscaled global climate models for use by public health practitioners at the regional and local level. Finally, we are increasing environmental health information for preparedness and response by exploring the link between climate change-related fluctuations in rainfall on the public health burden of gastrointestinal illness in the state of Wisconsin. The results of this research will enable public health managers and governmental agencies charged with preservation of our natural resources and protection of public health to better prevent and respond to waterborne disease threats from climate change.